Yeah, the recent most featured animation, so remember the various characters that made their peek-a-boo, obvious appearance in that movie?
list them if you know them, let's see how your OTAKU mode is XD.
Here's mine :
Disney
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One of the game portals in Game Central Station reads "TRON".
Tiny the T.Rex from Meet the Robinsons (Appearing as a Generic video game Dinosaur in Game Central Station, heavily resembling Sauron from Primal Rage)
Mickey Mouse on a Double U Dee's (WD's) billboard located behind Litwak's Arcade and Family Fun Center.
Disney Interactive Studios
Sora from Kingdom Hearts (In the Tapper scene, you can see an 8-Bit version of him in his Kingdom Hearts attire at the bottom-left corner of Tapper.)
Nintendo
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Bowser (King Koopa) from Super Mario Bros.
A Super Mushroom from Super Mario Bros.
Princess Daisy from Super Mario Bros.
Rosalina (Rosetta) from Super Mario Galaxy
(Note: Mario and Luigi, the protagonists of Super Mario Bros. were intended to have appeared in the film, voiced by Charles Martinet. However, the producers couldn't find a place to work them into the story, that felt right for their significance, along with paying a hefty licensing fee. However, Mario is mentioned by Fix-It Felix in the film.)
Sega
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Sonic the Hedgehog from Sonic the Hedgehog
Miles "Tails" Prower from Sonic the Hedgehog (Picture on a wall in Tapper's Bar.)
Dr. Robotnik (Eggman) from Sonic the Hedgehog
Amy Rose from Sonic the Hedgehog (on the arcade cabinet of Sonic the fighters alongside some other Sonic characters; her younger self from Sonic CD is used)
Neff from Altered Beast
Cyril the Zombie from House of the Dead
AiAi from Super Monkey Ball
Cyborg from Cyborg Justice
Mishaela from Shining Force
Capcom
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M. Bison (Vega) from Street Fighter II
Zangief from Street Fighter II
Chun-Li from Street Fighter II
Cammy from Super Street Fighter II
Ken from Street Fighter
Ryu from Street Fighter
Blanka from Street Fighter II
Beholder from Eye of the Beholder
The car-breaking bonus stage round from Street Fighter II
Sheng Long from the Street Fighter series (his name appears as a graffiti at the portal leading to Sugar Rush).
(Note: Dr. Wily from Mega Man was originally set to make an appearance in the Bad-Anon villains support group as shown in an early render image. However he was cut in the final version of the film and replaced with Smoke from Mortal Kombat.)
Midway
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Kano from Mortal Kombat
Smoke from Mortal Kombat
Paperboy from Paperboy
Bartender from Tapper
Namco
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Clyde from Pac-Man
Pac-Man from Pac-Man
Inky Ghost Monster from Pac-Man
Blinky Ghost Monster from Pac-Man
Pinky Ghost Monster from Pac-Man
Taizo from Dig Dug
A Pooka from Dig Dug
A Fygar from Dig Dug
Gottlieb
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Q*bert from Q*bert
Coily from Q*bert
Slick from Q*bert
Sam from Q*bert
Ugg from Q*bert
Square Enix
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Aerith from Final Fantasy VII (Refrenced and written in graffiti as Aerith Lives on a subway wall in Game Central Station.)
Lara Croft (Used by Wreck-it Ralph as a false name when trying to get past security.)
Konami
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Frogger from Frogger
Yuni from Dance Dance Revolution
Leonardo from Teenage Mutant Ninja Turtles (on the arcade cabinet of Teenage Mutant Ninja Turtles during the opening time-lapse shot)
An Exclamation mark (!) from Metal Gear
Atari
Paddle 1 and Paddle 2 from Pong
A racer from RoadBlasters
Taito
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An Alien Invader from Space Invaders (on a picture)
The Qix from Qix
Data East
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Peter Pepper from BurgerTime
Williams Electronics
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Knight and Ostrich from Joust
Blizzard North
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Diablo from Diablo (referred as "Satine")
Leroy Jenkins (Shown as Graffitti on the Terminal Wall of "Jenkins")
XD have fun spotting them